CN116458984A

CN116458984A - Electrode assembly with basket catheter having mechanical retainer and method therefor

Info

Publication number: CN116458984A
Application number: CN202310059061.4A
Authority: CN
Inventors: K·M·奥卡斯基; K·达塔; A·巴; T·阮
Original assignee: Biosense Webster Israel Ltd
Current assignee: Biosense Webster Israel Ltd
Priority date: 2022-01-20
Filing date: 2023-01-18
Publication date: 2023-07-21

Abstract

The disclosed technology includes a medical probe including a tubular shaft having an expandable basket assembly coupled to a distal end of the tubular shaft. The basket assembly may have at least one ridge extending along a longitudinal axis and configured to flex radially outward from the longitudinal axis when the basket assembly transitions from the collapsed to the expanded form. The basket assembly may include electrode assemblies, each attached to the spine. Each electrode assembly includes an electrode, and first and second electrically insulating portions that electrically isolate the electrode from the ridge. The electrode, the first electrically insulating portion, and the second electrically insulating portion interlock to the spine such that the plurality of electrode assemblies are prevented from sliding proximally or distally along the length of the spine.

Description

Electrode assembly with basket catheter having mechanical retainer and method therefor

Cross Reference to Related Applications

The present application claims the benefit of priority from U.S. c. ≡119, U.S. provisional patent application No. 63/301,146, previously filed on day 2022, month 1, 20, the entire contents of which provisional patent application is hereby incorporated by reference as if fully set forth herein.

Technical Field

The present invention relates generally to medical devices, and in particular to catheters having electrodes, and further, but not exclusively, to catheters suitable for inducing irreversible electroporation (IRE) of cardiac tissue.

Background

Arrhythmia, such as Atrial Fibrillation (AF), may occur when areas of heart tissue abnormally conduct electrical signals to adjacent tissue. This can disrupt the normal cardiac cycle and lead to arrhythmia. Certain protocols are used to treat cardiac arrhythmias, including surgically disturbing the source of the signals responsible for the arrhythmia and disturbing the conduction pathways for such signals. By selectively ablating cardiac tissue by applying energy through the catheter, it is sometimes possible to stop or alter the propagation of unwanted electrical signals from one portion of the heart to another.

Many current ablation methods in the art tend to utilize Radio Frequency (RF) electrical energy to heat tissue. RF ablation may have certain drawbacks such as an increased risk of thermal cell damage, which may lead to charring of tissue, burns, steam pops, phrenic nerve paralysis, pulmonary vein stenosis, and esophageal fistulae. Cryoablation is an alternative to RF ablation, which generally reduces the thermal risk associated with RF ablation. However, manipulating a cryoablation device and selectively applying cryoablation is generally more challenging than RF ablation; thus, cryoablation is not feasible in certain anatomical geometries that may be reached by an electrical ablation device.

Some ablation methods use irreversible electroporation (IRE) to ablate cardiac tissue using non-thermal ablation methods. IRE delivers short pulses of high pressure to the tissue and produces unrecoverable cell membrane permeabilization. The use of multi-electrode catheters to deliver IRE energy to tissue has previously been proposed in the patent literature. Examples of systems and devices configured for IRE ablation are disclosed in U.S. patent publications 2021/0169550A1, 2021/0169567A1, 2021/0169568A1, 2021/0161592A1, 2021/0196372A1, 2021/0177503A1 and 2021/0186604A1, each of which is incorporated by reference herein in its entirety as if fully set forth and attached in the appendix of priority application U.S. Pat. No. 63/301,146.

Areas of cardiac tissue may be mapped by the catheter to identify abnormal electrical signals. Ablation may be performed using the same or different catheters. Some example catheters include a plurality of ridges on which electrodes are disposed. The electrodes are typically attached to the ridges and secured in place by brazing, welding, or using an adhesive. However, due to the small size of the ridges and electrodes, brazing, welding, or adhering the electrodes to the ridges can be a laborious task, which increases manufacturing time and costs and increases the chance of the electrodes failing due to improper bonding or misalignment. What is needed, therefore, are systems and methods for attaching electrodes to the ridges of basket assemblies without the need for brazing, welding, or the use of adhesives.

Disclosure of Invention

According to one embodiment of the present invention, a medical probe is provided that includes an expandable basket assembly coupled to a distal end of a tubular shaft. The expandable basket assembly may include at least one spine and a plurality of electrode assemblies. The electrode assemblies may each include a first insulating portion and a second insulating portion, which may electrically insulate the electrode from the spine. The electrode, the first insulating portion, and the second insulating portion may interlock to the spine to prevent the electrode from sliding proximally or distally along the length of the spine. In this way, the presently disclosed techniques may be used to secure the electrode to the spine without the need for brazing, welding, or adhesives.

The disclosed technology includes a medical probe including a tubular shaft having a proximal end and a distal end. The tubular shaft may extend along a longitudinal axis. The medical probe may also include an expandable basket assembly coupled to the distal end of the tubular shaft.

The expandable basket assembly may include at least one ridge extending along the longitudinal axis and configured to flex radially outward from the longitudinal axis when the basket assembly transitions from the collapsed to the expanded form. The expandable basket assembly may include a plurality of electrode assemblies. Each electrode assembly of the plurality of electrode assemblies may be attached to at least one ridge. Each electrode assembly may include an electrode, a first electrically insulating portion electrically isolating the electrode from the corresponding ridge, and a second electrically insulating portion electrically isolating the electrode from the ridge. The electrode, the first electrically insulating portion and the second electrically insulating portion may be interlocked to the spine such that the plurality of electrode assemblies are prevented from sliding proximally or distally along the length of the spine.

The ridge may comprise a retaining ring to which respective ones of the plurality of electrode assemblies are interlocked. The electrode may include a protrusion configured to interlock with the second electrically insulating portion. The protrusions may extend through the retaining ring, thereby preventing the electrode assembly from sliding along the length of the spine. The protrusion may comprise a swaged fitting.

The first electrically insulating portion may comprise a first gasket and the second electrically insulating portion may comprise a second gasket. The first and second gaskets may be configured to prevent the electrode from contacting the ridge and to electrically isolate the electrode from the ridge. The second gasket may include a lip configured to extend inwardly into the retaining ring to prevent the electrode from contacting the ridge.

The first electrically insulating portion may be a first housing portion and the second electrically insulating portion may be a second housing portion. The first housing portion and the second housing portion may be configured to interlock to secure the electrode to the spine. The second housing portion may include a male connector and the first housing portion may include a female connector configured to receive the male connector and facilitate interlocking of the first housing portion with the second housing portion. Alternatively, the first housing portion may include a male connector and the second housing portion may include a female connector configured to receive the male connector and facilitate interlocking of the first housing portion with the second housing portion.

The first housing portion may include a rim configured to receive the electrode. The electrode may further comprise a base portion configured to retain the electrode in the rim of the first housing portion. The base portion may include an outer peripheral length that is greater than an inner peripheral length of the rim.

The electrodes may be electrically connected to wires of the medical probe. At least a portion of the wire may include a conductive core material having a first conductivity and a conductive cover material having a second conductivity less than the first conductivity. The conductive cover material may surround the conductive core material, and the insulating sheath may surround the conductive cover material. At least a portion of the wire may include a plurality of strands and an insulating sheath surrounding the plurality of strands. Each strand of the plurality of strands may include a conductive core material having a first conductivity and a conductive cover material having a second conductivity less than the first conductivity, respectively. The conductive cover material may surround the conductive core material.

The at least one ridge of the medical probe may comprise nitinol, cobalt chromium, or other suitable material.

The plurality of electrodes may be configured to deliver an electrical pulse for irreversible electroporation, the pulse having a peak voltage of at least 900 volts (V).

The at least one ridge may be configured to form an approximately spherical basket assembly or an approximately oblate spheroid basket assembly when in the expanded form.

The medical probe may also include an irrigation opening that may be configured to deliver irrigation fluid to the plurality of electrodes.

The medical probe may further include electrically insulating sheaths each disposed between at least one ridge and a respective electrode of the plurality of electrodes, thereby electrically isolating the plurality of electrodes from the plurality of ridges. Each of the plurality of electrically insulating jackets may include a first lumen and a second lumen. The first lumen may be configured to receive a first wire and the second lumen may be configured to receive a corresponding ridge. Furthermore, the cross-sectional shape of each electrically insulating sheath may be a substantially trapezoidal shape.

The disclosed technology may include a method of constructing a medical probe. The method may include aligning the electrode, the first insulating portion, and the second insulating portion. The method may include placing a ridge of the basket conduit between the first and second insulating portions and interlocking the electrode, the first and second insulating portions together to secure the electrode to the ridge. The electrode, the first insulating portion, and the second insulating portion may be secured to the spine such that the first insulating portion and the second insulating portion electrically isolate the electrode from the spine and such that the electrode, the first insulating portion, and the second insulating portion are prevented from sliding proximally or distally along the length of the respective spine.

Interlocking the electrode, the first insulating portion, and the second insulating portion together may include interlocking a portion of at least one of the electrode, the first insulating portion, and the second insulating portion through the aperture of the retaining ring of the ridge. The method may include aligning the electrode, the first insulating portion, and the second insulating portion with the retaining ring.

Interlocking the electrode, the first insulating portion, and the second insulating portion together may include interlocking a protrusion of the electrode with the second insulating portion. The method may include forming a swaged fitting on the protrusion to interlock the electrode with the second insulating portion. Interlocking the electrode, the first insulating portion, and the second insulating portion together may include extending the protrusion through the retaining ring, thereby preventing the electrode from sliding proximally or distally along the length of the spine.

The first insulating portion may include a first insulating washer and the second insulating portion may include a second insulating washer. The method may include positioning the first insulating washer and the second insulating washer such that the electrode is electrically isolated from the ridge.

Interlocking the electrode, the first insulating portion, and the second insulating portion together may include extending a lip of the second insulating gasket inward into the retaining ring, thereby preventing the electrode from contacting the ridge.

The first insulating portion may include a first insulating housing portion and the second insulating portion may include a second insulating housing portion. Interlocking the electrode, the first insulating portion, and the second insulating portion together may include interlocking the first insulating housing portion and the second insulating housing portion to secure the electrode to the spine.

The second insulative housing portion may include a male connector and the first insulative housing portion may include a female connector configured to receive the male connector and facilitate interlocking of the first insulative housing portion with the second insulative housing portion.

The first insulating housing portion may include a rim configured to receive the electrode. Interlocking the electrode, the first insulating portion, and the second insulating portion together may include retaining the base portion of the electrode in the rim. The base portion may include an outer peripheral length that is greater than an inner peripheral length of the rim.

The method may include electrically connecting the electrode to a wire of the medical probe. At least a portion of the wire may include a conductive core material having a first conductivity and a conductive cover material having a second conductivity less than the first conductivity. The conductive cover material may surround the conductive core material, and the insulating sheath may surround the conductive cover material. At least a portion of the wire may include a plurality of strands and an insulating sheath surrounding the plurality of strands. Each strand of the plurality of strands may include a conductive core material having a first conductivity and a conductive cover material having a second conductivity less than the first conductivity, respectively. The conductive cover material may surround the conductive core material.

Each of the plurality of ridges of the medical probe may comprise nitinol, cobalt chromium, or other suitable material.

Each of the plurality of ridges may be configured to form a generally spherical basket assembly or a generally oblate spheroid basket assembly when in the expanded form.

The medical probe may further include a plurality of electrically insulating sheaths each disposed between a respective one of the plurality of ridges and a respective one of the plurality of electrodes, thereby electrically isolating the plurality of electrodes from the plurality of ridges. Each of the plurality of electrically insulating jackets may include a first lumen and a second lumen. The first lumen may be configured to receive a first wire and the second lumen may be configured to receive a corresponding ridge. Furthermore, the cross-sectional shape of each electrically insulating sheath may be a substantially trapezoidal shape.

Drawings

FIG. 1 is a schematic illustration of a medical system including a medical probe having a distal end including a basket assembly with electrodes according to an embodiment of the present invention;

FIG. 2A is a schematic illustration showing a perspective view of a medical probe in an expanded form according to an embodiment of the invention;

FIG. 2B is a schematic illustration showing a side view of a medical probe in a collapsed form in accordance with the disclosed technology;

FIGS. 3A and 3B are exploded views of a spine showing a tubular shaft and basket assembly to illustrate a schematic illustration of how the spine may be assembled with the tubular shaft, according to an embodiment of the present invention;

fig. 4A and 4B are schematic illustrations showing perspective views of electrodes attached to ridges according to embodiments of the invention;

FIG. 5 is a schematic illustration showing a side exploded view of an electrode assembly and a ridge according to an embodiment of the invention;

fig. 6 is a schematic illustration showing a perspective exploded view of an electrode assembly and a ridge according to an embodiment of the invention;

FIG. 7A is a schematic illustration showing a top view of a ridge according to another embodiment of the invention;

FIG. 7B is a schematic illustration showing a side view of an electrode according to another embodiment of the invention;

FIG. 7C is a schematic illustration showing a perspective view of a gasket according to another embodiment of the invention;

FIG. 7D is a schematic illustration showing a perspective view of another gasket in accordance with another embodiment of the invention;

fig. 8A and 8B are schematic illustrations showing a perspective view of an electrode assembly according to another embodiment of the present invention;

fig. 9 is a schematic illustration showing an exploded view of an electrode assembly according to another embodiment of the present invention;

fig. 10A and 10B are schematic illustrations showing a perspective view of a housing portion of an electrode assembly according to another embodiment of the present invention;

fig. 10C and 10D are schematic illustrations showing perspective views of another housing portion of an electrode assembly according to another embodiment of the present invention;

FIGS. 11A and 11B are schematic illustrations showing various insulating sheaths of a given medical device according to embodiments of the invention;

FIGS. 12A and 12B are schematic illustrations showing a side view of a ridge of a given medical device, according to an embodiment of the invention;

FIGS. 13A and 13B are schematic illustrations showing cross-sectional views of a given line of a medical probe according to embodiments of the invention;

fig. 14 is a flow chart illustrating a method of assembling a basket assembly according to an embodiment of the present invention.

Detailed Description

The following detailed description should be read with reference to the drawings, in which like elements in different drawings are numbered identically. The drawings, which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of the invention. The detailed description illustrates by way of example, and not by way of limitation, the principles of the invention. This description will clearly enable one skilled in the art to make and use the invention, and describes several embodiments, adaptations, variations, alternatives and uses of the invention, including what is presently believed to be the best mode of carrying out the invention.

As used herein, the term "about" or "approximately" for any numerical value or range indicates a suitable dimensional tolerance that allows a collection of parts or components to achieve the intended purpose thereof as described herein. More specifically, "about" or "approximately" may refer to a range of values of ±20% of the recited values, for example "about 90%" may refer to a range of values of 71% to 110%. In addition, as used herein, the terms "patient," "host," "user," and "subject" refer to any human or animal subject, and are not intended to limit the system or method to human use, but use of the subject invention in a human patient represents a preferred embodiment. Likewise, the term "proximal" refers to a location closer to an operator or physician, while "distal" refers to a location further from the operator or physician.

As discussed herein, the vasculature of a "patient," "recipient," "user," and "subject" may be the vasculature of a human or any animal. It should be understood that the animal may be of any suitable type including, but not limited to, a mammal, a veterinary animal, a livestock animal or a companion animal, and the like. For example, the animal may be a laboratory animal (e.g., rat, dog, pig, monkey, etc.) specifically selected to have certain characteristics similar to humans. It should be appreciated that the subject may be, for example, any suitable human patient.

As discussed herein, an "operator" may include a doctor, surgeon, technician, scientist, or any other individual or delivery meter device associated with delivering a multi-electrode catheter for treating drug refractory atrial fibrillation to a subject.

As discussed herein, the term "ablation" when referring to the devices and corresponding systems of the present disclosure refers to components and structural features configured to reduce or prevent the generation of unstable cardiac signals in cells by utilizing non-thermal energy, such as irreversible electroporation (IRE), interchangeably referred to in the present disclosure as Pulsed Electric Field (PEF) and Pulsed Field Ablation (PFA). "ablation" as used throughout the present disclosure, when referring to the devices and corresponding systems of the present disclosure, refers to non-thermal ablation of cardiac tissue for certain conditions, including, but not limited to, arrhythmia, atrial flutter ablation, pulmonary vein isolation, supraventricular tachycardia ablation, and ventricular tachycardia ablation. The term "ablation" also includes known methods, devices and systems for effecting various forms of ablation of body tissue as understood by those skilled in the relevant art.

As discussed herein, the terms "bipolar" and "monopolar" when used in reference to an ablation scheme describe an ablation scheme that differs in terms of current path and electric field distribution. "bipolar" refers to an ablation protocol that utilizes a current path between two electrodes, both of which are positioned at a treatment site; the current density and the current flux density at each of the two electrodes are typically approximately equal. "monopolar" refers to an ablation procedure utilizing a current path between two electrodes, where one electrode having a high current density and a high electrical flux density is positioned at the treatment site and a second electrode having a relatively lower current density and a lower electrical flux density is positioned away from the treatment site.

As discussed herein, the terms "biphasic pulse" and "monophasic pulse" refer to the corresponding electrical signals. A "biphasic pulse" refers to an electrical signal having a positive voltage phase pulse (referred to herein as the "positive phase") and a negative voltage phase pulse (referred to herein as the "negative phase"). "monophasic pulse" refers to an electrical signal having only a positive phase or only a negative phase. Preferably, the system providing biphasic pulses is configured to prevent the application of a direct current voltage (DC) to the patient. For example, the average voltage of the biphasic pulse may be zero volts relative to ground or other common reference voltage. Additionally or alternatively, the system may include a capacitor or other protective component. Voltage amplitudes of biphasic and/or monophasic pulses are described herein, it being understood that the expressed voltage amplitudes are absolute values of the approximate peak amplitudes of each of the positive voltage phase and/or the negative voltage phase. Each phase of the biphasic pulse and the monophasic pulse preferably has a square shape with a substantially constant voltage amplitude during a substantial portion of the phase duration. The phases of the biphasic pulse are separated in time by an inter-phase delay. The inter-phase delay duration is preferably less than or approximately equal to the duration of the phase of the biphasic pulse. The inter-phase delay duration is more preferably about 25% of the duration of the phase of the biphasic pulse.

As discussed herein, the terms "tubular" and "tube" are to be understood in a broad sense and are not limited to structures that are right circular cylinders or that are entirely circumferential in cross-section or have a uniform cross-section throughout their length. For example, the tubular structure is generally shown as a substantially right circular cylinder structure. However, the tubular structure may have a tapered or curved outer surface without departing from the scope of the present disclosure.

As used herein, the term "temperature rating" is defined as the maximum continuous temperature that a component can withstand during its lifetime without causing thermal damage such as melting or thermal degradation (e.g., charring and chipping) of the component.

The present disclosure relates to systems, methods, or uses and devices utilizing an end effector having electrodes attached to ridges. The exemplary systems, methods, and devices of the present invention may be particularly useful for IRE ablation of cardiac tissue to treat cardiac arrhythmias. Ablation energy is typically provided to the heart tissue by an end portion of the catheter that can deliver ablation energy along the tissue to be ablated. Some example catheters include a three-dimensional structure at the tip portion and are configured to apply ablation energy from various electrodes positioned on the three-dimensional structure. Fluoroscopy may be used to visualize the ablation procedure in combination with such exemplary catheters.

Cardiac tissue ablation using thermal techniques such as Radio Frequency (RF) energy and cryoablation to correct for a malfunctioning heart is a well-known procedure. Typically, for successful ablation using thermal techniques, the cardiac electrode potentials need to be measured at various locations in the myocardium. Furthermore, temperature measurements during ablation provide data that enables ablation efficacy. Typically, for ablation protocols using thermal ablation, electrode potential and temperature are measured before, during, and after the actual ablation.

RF methods may have risks that may lead to charring of tissue, burns, steam bursts, phrenic nerve paralysis, pulmonary vein stenosis, and esophageal fistulae. Cryoablation is an alternative to RF ablation, which may reduce some of the thermal risks associated with RF ablation. However, manipulating a cryoablation device and selectively applying cryoablation is generally more challenging than RF ablation; thus, cryoablation is not feasible in certain anatomical geometries that may be reached by an electrical ablation device.

IRE as discussed in this disclosure is a non-thermal cell death technique that may be used for atrial arrhythmia ablation. To ablate using IRE/PEF, biphasic voltage pulses are applied to disrupt the cellular structure of the myocardium. The biphasic pulse is non-sinusoidal and can be tuned to target cells based on the electrophysiology of the cells. In contrast, to ablate using RF, a sinusoidal voltage waveform is applied to generate heat at the treatment region, heating all cells indiscriminately in the treatment region. Thus, IRE has the ability to avoid adjacent heat sensitive structures or tissue, which would be beneficial in reducing the possible complications known to be affected by ablation or separation modalities. In addition or alternatively, monophasic pulses may be used.

Electroporation can be induced by applying a pulsed electric field across the biological cells to cause reversible (temporary) or irreversible (permanent) creation of pores in the cell membrane. Upon application of a pulsed electric field, the cell has a transmembrane electrostatic potential that rises above the static potential. Electroporation is reversible when the transmembrane electrostatic potential remains below the threshold potential, meaning that the pores can close when the applied pulsed electric field is removed and the cells can repair and survive themselves. If the transmembrane electrostatic potential rises above the threshold potential, electroporation is irreversible and the cell becomes permanently permeable. Thus, cells die due to a loss of homeostasis and usually die by apoptosis. Typically, different types of cells have different threshold potentials. For example, cardiac cells have a threshold potential of about 500V/cm, whereas for bone, the threshold potential is 3000V/cm. These differences in threshold potential allow IRE to selectively target tissue based on the threshold potential.

The solutions of the present disclosure include systems and methods for applying electrical signals from catheter electrodes positioned near myocardial tissue, preferably by applying a pulsed electric field effective to induce electroporation in myocardial tissue. The systems and methods can effectively ablate targeted tissue by inducing irreversible electroporation. In some examples, the systems and methods are effective to induce reversible electroporation as part of a diagnostic procedure. Reversible electroporation occurs when the electricity applied with the electrodes is below the electric field threshold of the target tissue that allows cell repair. Reversible electroporation does not kill cells, but allows the physician to view the effect of reversible electroporation on the electrical activation signal near the target site. Exemplary systems and methods for reversible electroporation are disclosed in U.S. patent publication 2021/0162210, which is incorporated herein by reference in its entirety as if fully set forth and set forth in the appendix of priority application U.S. 63/301,146.

The pulsed electric field and its effectiveness in inducing reversible and/or irreversible electroporation may be affected by the physical parameters of the system and the biphasic pulse parameters of the electrical signal. Physical parameters may include electrode contact area, electrode spacing, electrode geometry, and the like. Examples presented herein generally include physical parameters suitable for effectively inducing reversible and/or irreversible electroporation. Biphasic pulse parameters of an electrical signal may include voltage amplitude, pulse duration, pulse-to-pulse delay, inter-pulse delay, total applied time, delivered energy, and the like. In some examples, parameters of the electrical signal may be adjusted to induce both reversible and irreversible electroporation given the same physical parameters. Examples of various ablation systems and methods including IRE are provided in U.S. patent publications 2021/0169550A1, 2021/0169567A1, 2021/0169568A1, 2021/0161592A1, 2021/0196372A1, 2021/0177503A1 and 2021/0186604A1, each of which is incorporated by reference herein in its entirety as if fully set forth and attached in the appendix of priority application U.S. Pat. No. 63/301,146.

To deliver Pulsed Field Ablation (PFA) in an IRE (irreversible electroporation) procedure, the surface area of the electrode in contact with the tissue being ablated should be sufficiently large. As described below, the medical probe includes a flexible insertion tube having a proximal end and a distal end, and a basket assembly located at the distal end of the flexible insertion tube. The basket assembly includes at least one spine and a plurality of electrode assemblies. Each electrode assembly may be configured to interlock with the spine to prevent the spine from sliding proximally or distally along the length of the spine.

Fig. 1 is a schematic illustration of a medical system 20 including a medical probe 22 and a console 24 according to an embodiment of the present invention. Medical system 20 may be based on, for example, a system produced by Biosense Webster inc (31Technology Drive,Suite 200,Irvine,CA 92618USA)The system. In the embodiments described below, the medical probe 22 may be used for diagnostic or therapeutic treatment, such as for performing an ablation procedure in the heart 26 of the patient 28. Alternatively, the medical probe 22 may be used for other therapeutic and/or diagnostic purposes in the heart or other body organs, mutatis mutandis.

The medical probe 22 includes a flexible insertion tube 30 and a handle 32 coupled to a proximal end of the insertion tube. During a medical procedure, a medical professional 34 may insert the probe 22 through the vascular system of the patient 28 such that the distal end 36 of the medical probe enters a body cavity, such as a chamber of the heart 26. After distal end 36 enters the chamber of heart 26, medical professional 34 may deploy basket assembly 38 attached to distal end 36. Basket assembly 38 may include a plurality of electrodes 40 attached to a plurality of ridges, as described below with reference to the description of fig. 2A and 2B. To begin performing a medical procedure, such as irreversible electroporation (IRE) ablation, the medical professional 34 can manipulate the handle 32 to position the distal end 36 such that the electrode 40 engages the cardiac tissue at the desired location or locations. Upon positioning distal end 36 such that electrode 40 engages heart tissue, medical professional 34 can activate medical probe 22 such that electrode 40 delivers an electrical pulse to perform IRE ablation.

In the configuration shown in fig. 1, the console 24 is connected by a cable 42 to a body surface electrode that typically includes an adhesive skin patch 44 attached to the patient 28. The console 24 includes a processor 46 that, in conjunction with a tracking module 48, determines the position coordinates of the distal end 36 within the heart 26. The position coordinates may be determined based on electromagnetic position sensor output signals provided from the distal portion of the catheter when the generated magnetic field is present. Additionally or alternatively, the location coordinates may be based on impedance and/or current measured between the adhesive skin patch 44 and the electrode 40 attached to the basket assembly 38. In addition to functioning as a position sensor during a medical procedure, the electrode 40 may perform other tasks, such as ablating tissue in the heart.

As described above, the processor 46 may be coupled with the tracking module 48 to determine the location coordinates of the distal end 36 within the heart 26 based on the impedance and/or current measured between the adhesive skin patch 44 and the electrode 40. Such determination is typically after a calibration procedure has been performed that correlates the impedance or current with the known position of the distal end. While the embodiments presented herein describe electrodes 40 that are preferably configured to deliver IRE ablation energy to tissue in heart 26, it is considered to be within the spirit and scope of the present invention to configure electrodes 40 to deliver any other type of ablation energy to tissue in any body cavity. Furthermore, while described in the context of electrodes 40 configured to deliver IRE ablation energy to tissue in heart 26, those skilled in the art will appreciate that the disclosed techniques may be applicable to electrodes used to map and/or determine various characteristics of an organ or other portion of the body of patient 28.

The processor 46 may include real-time noise reduction circuitry 50, typically configured as a Field Programmable Gate Array (FPGA), and analog-to-digital (a/D) signal conversion integrated circuitry 52. The processor may be programmed to execute one or more algorithms and use the characteristics of circuitry 50 and 52 and the modules to enable the medical professional 34 to perform an IRE ablation procedure.

The console 24 also includes an input/output (I/O) communication interface 54 that enables the console 24 to communicate signals from and/or to the electrode 40 and the adhesive skin patch 44. In the configuration shown in fig. 1, console 24 also includes IRE ablation module 56 and switching module 58.

IRE ablation module 56 is configured to generate IRE pulses having peak power in the range of tens of kilowatts. In some examples, electrode 40 is configured to deliver an electrical pulse having a peak voltage of at least 900 volts (V) and in some cases 1100V or higher. Medical system 20 performs IRE ablation by delivering IRE pulses to electrodes 40. Preferably, medical system 20 delivers biphasic pulses between electrodes 40 on the ridges. Additionally or alternatively, medical system 20 delivers monophasic pulses between at least one of electrodes 40 and the skin patch.

Where irrigation is desired, the system 20 supplies irrigation fluid (e.g., saline solution) to the distal end 36 and to the electrode 40 via a channel (not shown) in the insertion tube 30. The console 24 includes a flushing module 60 to monitor and control flushing parameters such as pressure and temperature of the flushing fluid.

Based on the signals received from the electrode 40 and/or the adhesive skin patch 44, the processor 46 may generate an electroanatomical map 62 showing the position of the distal end 36 within the patient. During a procedure, the processor 46 may present the map 62 to the medical professional 34 on the display 64 and store data representing the electroanatomical map in the memory 66. Memory 66 may include any suitable volatile memory and/or nonvolatile memory, such as random access memory or a hard disk drive.

In some embodiments, medical professional 34 can manipulate map 62 using one or more input devices 68. In alternative embodiments, display 64 may include a touch screen that may be configured to accept input from medical professional 34 in addition to presenting map 62.

Fig. 2A is a schematic illustration showing a perspective view of a medical probe 22 having a basket assembly 38 in an expanded form when unconstrained, such as by being pushed out of an insertion tube lumen 80 at the distal end 36 of the insertion tube 3. Fig. 2B shows the basket assembly in collapsed form within the insertion tube 30. In the expanded form (fig. 2A), the ridges 214 curve radially outward, while in the collapsed form (fig. 2B), the ridges are generally disposed along the longitudinal axis 86 of the insertion tube 30.

As shown in fig. 2A, basket assembly 38 includes a plurality of flexible ridges 214 formed at and connected at the ends of tubular shaft 84. During a medical procedure, the medical professional 34 may deploy the basket assembly 38 by extending the tubular shaft 84 from the insertion tube 30, thereby causing the basket assembly 38 to exit the insertion tube and transition to the expanded form. The ridges 214 may have an oval (e.g., circular) or rectangular (which may appear flat) cross-section and comprise a flexible, resilient material (e.g., a shape memory alloy such as nickel titanium (also known as nitinol), cobalt chromium, or any other suitable material).

In embodiments described herein, electrode 40 may be configured to deliver ablation energy (RF and/or IRE) to tissue in heart 26. Additionally or alternatively, the electrodes may also be used to determine the position of basket assembly 38 and/or measure physiological characteristics, such as local surface potentials at corresponding locations on tissue in heart 26. Electrode 40 may be biased such that a greater portion of electrode 40 faces outward from basket assembly 39 such that electrode 40 delivers a greater amount of electrical energy outward away from basket assembly 38 (i.e., toward heart 26 tissue) than inward toward basket assembly 38.

Examples of materials that are ideally suited for forming electrode 40 include gold, platinum, and palladium (and their corresponding alloys). These materials also have a high thermal conductivity that allows the minimal heat generated on the tissue (i.e., ablation energy delivered to the tissue) to be conducted through the electrode to the back of the electrode (i.e., the portion of the electrode on the inside of the ridge) and then to the blood pool in heart 26.

Basket assembly 38 has a distal end 94 and includes a stem 96 that extends longitudinally from distal end 36 of tubular shaft 84 toward distal end 94 of basket assembly 38. As described above, the console 24 includes an irrigation module 60 that delivers irrigation fluid to the distal end 36. Handle 96 includes a plurality of irrigation openings 98, wherein each given irrigation opening 98 may be angled to spray or otherwise disperse irrigation fluid to tissue in a given electrode 40 or heart 26.

Since the electrode 40 does not include irrigation openings that deliver irrigation fluid, the configuration described above enables heat transfer from the tissue to the portion of the electrode on the inside of the ridge 214 (i.e., during an ablation procedure), and the electrode 40 may be cooled by aligning the irrigation fluid with the portion of the electrode 40 on the inside of the ridge 214 via the irrigation openings 98.

Fig. 3A and 3B are exploded views of the spine 214 showing the tubular shaft 84 and basket assembly to provide a schematic illustration of one example of how the spine 214 may be assembled with the tubular shaft 84 in accordance with an embodiment of the present invention. As shown in fig. 3A, the ridges 214 may be formed from a single sheet of planar material to form a generally star shape. In other words, the ridges 214 may be formed from a single sheet of planar material such that the ridges 214 converge toward the center intersection 211. The intersection 211 may be a sheet of solid material (as shown in fig. 3A) or include one or more holes (as shown in fig. 3B).

The spine 214 may be folded or otherwise bent such that the proximal end 216 of the spine 214 may be inserted into the distal end 85 of the tubular shaft 84, as shown in fig. 3B. Although not shown in fig. 3A and 3B, it should be understood that the electrode 40 may be attached to the spine 214 prior to insertion of the spine into the tubular shaft 84 to form the basket assembly 38. As previously described, the ridges 214 may comprise a flexible, resilient material (e.g., a shape memory alloy such as nickel titanium, also known as nitinol) that may transform the basket assembly 38 from its collapsed form (as shown in FIG. 2B) to its expanded form (as shown in FIG. 2A) when the basket assembly 38 is deployed from the insertion tube 30. As will become apparent throughout this disclosure, the ridges 214 may be electrically isolated from the electrode 40 to prevent arcing from the electrode 40 to the ridges 214.

As will be appreciated by those skilled in the art having the benefit of this disclosure, the basket assembly 38 shown in fig. 2A-3B having ridges 214 formed from a single sheet of planar material and converging at a center intersection is provided for illustrative purposes only and the disclosed techniques may be applied to other configurations of basket assembly 38. For example, the disclosed techniques may be applied to basket assemblies 38 formed of a single spine 214 or multiple spines 214, with each spine 214 attached at both ends. In other examples, the basket assembly 38 may include a central hub connecting the plurality of ridges 214 together at the distal end 94 of the basket assembly 38. In still other examples, basket assembly 38 may include a single spine 214 configured to form a spiral, a plurality of spines 214 configured to form one or more tripods, or any other shape of basket assembly 38. Likewise, the spine assembly 210 may be formed by laser cutting a cylindrical hollow stock material with a laser mounted for rotation about (and translation to) a longitudinal axis of the cylindrical stock material while cutting through the cylindrical stock material. Thus, while fig. 2A and 3B illustrate a particular configuration of basket assembly 38, the disclosed techniques should not be construed as limited thereto.

Turning now to fig. 4A-10D, various examples of electrode assemblies 300, 800 will be described. As will become apparent throughout this disclosure, the electrode assemblies 300, 800 may be configured to attach the electrodes 340, 840 to the spine 214 and prevent the electrodes 340, 840 from sliding proximally or distally along the length of the spine 214. In general, the electrode assembly 300, 800 may include an electrode 340, 840, a first electrically insulating portion (i.e., the first gasket 350 or the first insulating housing portion 870, as described herein), and a second electrically insulating portion (i.e., the second gasket 350 or the second insulating housing portion 880, as described herein). The first and second insulating portions may electrically isolate the electrodes 340, 840 from the spine 214. As will be appreciated, although the electrode assemblies 300, 800 are described as having a first electrically insulating portion and a second electrically insulating portion, those skilled in the art will appreciate that insulating coatings may be used in addition to or in lieu of the insulating portions described herein.

The electrode assemblies 300, 800 are preferably asymmetric with respect to the plane of the spine such that the electrode 340 presents a conductive surface area facing outwardly from the perimeter of the basket of the catheter and an insulating surface facing inwardly from the perimeter of the basket. Furthermore, as will be appreciated by those skilled in the art, the electrodes 340, 840 may be identical to or in lieu of the electrode 40 previously described herein. That is, electrode assemblies 300, 800 are examples of the present disclosure that may be used to attach electrodes 340, 840 to ridges 214 so that electrodes 340, 840 perform the same or similar functions as electrodes 40 described herein (e.g., delivering IRE ablation energy to cardiac tissue). Those skilled in the art will appreciate that the electrode assemblies 300, 800 described herein are provided for illustrative purposes, and other electrode assemblies having similar features may be reasonably construed to fall within the scope of the present disclosure. Accordingly, the present disclosure should not be construed as limited to the particular electrode assemblies 300, 800 shown in fig. 4A-10D and described herein.

Fig. 4A and 4B are schematic illustrations showing a perspective view of an electrode assembly 300 attached to a ridge 214, according to an embodiment of the invention. The electrode assembly 300 may include an electrode 340, a first gasket 350, and a second gasket 360. Electrode 340 may include conductive materials (e.g., gold, platinum, and palladium (and their corresponding alloys)) as described with respect to electrode 40. The first gasket 350 and the second gasket 360 may be made of a biocompatible electrically insulating material such as polyetherimide (Ultem), polyimide, polyetheretherketone (PEEK), polytetrafluoroethylene (PTFE), fluorinated Ethylene Propylene (FEP), or the like. In addition, the first and second gaskets 350 and 360 may include a filler material such as PTFE (for insulation), boron nitride (for insulation), diamond (for thermal conduction), and the like. In this way, the first and second washers 350, 360 may be configured to electrically isolate the electrode 340 from the ridge 214 to prevent or reduce arcing between the electrode 340 and the ridge 214.

The electrode 340, the first gasket 350, and the second gasket 360 may be configured to interlock with each other to form the electrode assembly 300. Further, as will be described in greater detail herein, the electrode 340, the first gasket 350, and the second gasket 360 may be configured to interlock with the spine 214 to prevent the electrode assembly 300 from sliding proximally or distally along the length of the spine 214. To help prevent the electrode assembly 300 from sliding proximally or distally along the length of the spine 214, the spine 214 may include a retaining ring 330, which may be a ring formed in the spine 214 that includes a hole 332 through which a portion of the electrode assembly 300 may pass. The retaining ring 330 may be better seen in fig. 6 and 7A and described with respect to fig. 6 and 7A.

Fig. 5 is a schematic illustration showing a front exploded view of the electrode assembly 300 and the ridge 214, and fig. 6 is a schematic illustration showing a perspective exploded view of the electrode assembly 300 and the ridge 214, according to an embodiment of the present invention. As shown in fig. 5 and 6, the electrode 340 and the first gasket 350 may be positioned on a first side of the spine 214, while the second gasket 360 may be positioned on a second side of the spine 214. Thus, when the electrode 340, the first gasket 350, and the second gasket 360 are pushed together to attach to the spine 214, the spine 214 may be positioned between portions of the electrode assembly 300. Further, as shown in fig. 6, at least a portion of the electrode 340 may be configured to pass through the aperture 332 of the retaining ring 330 to help secure the electrode assembly 300 to the spine 214. In other words, since at least a portion of the electrode 340 may pass through the retaining ring 330, the electrode assembly 300 may be secured together by the retaining ring 330 such that the electrode assembly 300 is prevented from disengaging from or sliding along the ridge 214.

The electrode assembly 300 may be secured in place by including mechanical interference that prevents separation of the electrode assembly 300 once secured together. For example, the electrode 340 and at least the second gasket 360 may be configured to form an interference fit together when pressed together to prevent the electrode 340 from becoming detached from the second gasket 360. For example, the outer diameter of the protrusion 342 of the electrode 340 may be slightly larger than the inner diameter of the bore 362 through the second gasket 360 to form an interference fit between the electrode 340 and the second gasket 360 when pressed together.

As another example, the electrode 340 may include a swaged fitting 344 that may be sized to secure the electrode assembly 300 in place once the electrode 340 is engaged with the second gasket 360. The swage fitting 344 may be formed when the electrode 340 and the second washer 360 are pushed together using a tool suitable for forming the swage fitting. Alternatively or additionally, swage fitting 344 may be formed prior to pressing electrode 340 and second washer 360 together. For example, the swage fitting 344, the second washer 360, or both may include an elastic material that may deflect as the swage fitting 344 is pushed through the bore 362 of the second washer 360. The swage fitting 344 may then be returned (or nearly returned) to its original configuration after being pushed through the bore 362 of the second washer 360 so that the electrode assembly 300 is secured in place. In other words, both the swage fitting 344 and the aperture 362 of the second gasket 360 may be configured to allow a portion of the electrode 340 to pass through the aperture 362 of the second gasket 360 in a first direction while preventing the electrode 340 from passing through the aperture 362 in a second direction and becoming disengaged from the second gasket 360 after assembly. As will be appreciated by those skilled in the art, although the electrode assembly 300 is shown with a second gasket 360 having an aperture 362 configured to receive at least a portion of the electrode 340 to secure the electrode assembly 300 in place, the disclosed techniques are not so limited. As one non-limiting example, the configuration of the electrode assembly 300 may be switched, and the electrode 340 may include a hole (or holes) configured to receive a protrusion of the second gasket 360 to secure the electrode assembly 300 in place.

Fig. 7A is a schematic illustration showing a top view of the ridge 214. As shown in fig. 7A, the ridge 214 may include a retaining ring 330, which may be a simple ring or circle formed in the ridge 214. The retaining ring 330 may include a hole 332 through or through which at least a portion of the electrode assembly 300 may be positioned. As one example, and as shown in fig. 7B, the electrode 340 may include a protrusion 342 that may be configured to extend through the aperture 332 of the retaining ring 330 when the electrode assembly 300 is attached to the spine 214. In this manner, when the electrode 340 is engaged with the second gasket 360, the electrode assembly 300 may be prevented from sliding along the ridge 214 or otherwise disengaging from the ridge 214. As shown in fig. 7B, the protrusion 342 of the electrode 340 may extend outwardly from the electrode 340 and include a swage fitting 344 as previously described. The tab 342 may be sized to fit within the aperture 332 of the retaining ring 330 and the aperture 352 of the first washer 350 and the aperture 362 of the second washer 360. Electrode 340 may be connected to a wire passing through the back side of electrode 340 near swage fitting 344. For example, the wire may be welded, crimped, soldered, or otherwise connected to the electrode by passing through the protrusion 342 and connecting to the inner surface of the electrode 340.

As shown in fig. 7D, the second washer 360 may further include a lip 364, which may be configured to extend through the aperture 332 of the retaining ring 330. Lip 364 may also be sized to extend through aperture 352 of first gasket 350 such that electrode 340 is electrically isolated from ridge 214.

Although the electrode assembly 300 and its components are shown in fig. 4A-7D as having a generally cylindrical shape, those skilled in the art will appreciate that electrode assemblies 300 having other shapes are contemplated. For example, the electrode assembly 300 may include a generally rectangular, triangular, polygonal, oval, or any other suitable shape without departing from the scope of the present disclosure. Further, the retaining ring 330, the tab 342 of the electrode 340, the aperture 352 of the first gasket 350, and the aperture 362 of the second gasket 360 may each comprise a shape other than the generally circular shape shown (i.e., generally rectangular, triangular, polygonal, elliptical, or any other suitable shape). Thus, although electrode assembly 300 is illustrated as having a particular shape and configuration, those skilled in the art will appreciate that electrode assembly 300 may include a variety of other shapes and configurations depending on the particular application without departing from the scope of the present disclosure.

Turning now to fig. 8A-10D, another exemplary electrode assembly 800 is shown and described herein. Electrode assembly 800 may be configured to perform similar functions as electrode assembly 300 described herein. That is, electrode assembly 800 may be configured to secure electrode 840 to spine 214, and electrode 840 may be configured to deliver IRE ablation energy to cardiac tissue, among other features described herein. The electrode assembly 800 may include an electrode 840, a first insulative housing portion 870, and a second insulative housing portion 880. Electrode 840 may include conductive materials (e.g., gold, platinum, and palladium (and their corresponding alloys)) as described with respect to electrode 40 and electrode 340. The first insulative housing portion 870 and the second insulative housing portion 880 may include materials that may electrically insulate the electrode 840 from the spine 214. For example, the first insulative housing portion 870 and the second insulative housing portion 880 can be made of biocompatible electrically insulating materials such as Ultem, PEEK, liquid crystal polymers (Vectra/Zenite), polycarbonate, and the like. The first insulative housing portion 870 and the second insulative housing portion 880 may include a filler material, such as fiberglass having a concentration of about 2% to 30%. In this manner, the first insulative housing portion 870 and the second insulative housing portion 880 may be configured to electrically isolate the electrode 840 from the spine 214 to prevent or reduce arcing between the electrode 840 and the spine 214.

Electrode assembly 800 may include a channel 890 through which at least a portion of ridge 214 may pass. For example, the channel 890 may be sized to at least partially receive the spine 214 such that the electrode assembly 800 may be secured to the spine 214 by clamping around the spine 214. For example, although not shown in fig. 9, the spine 214 may be placed between the electrode 840 and the second insulative housing portion 880 such that the electrode assembly 800 may be secured around the spine 214 when the electrode assembly 800 is pushed together for assembly. To further secure electrode assembly 800 to the spine, the cross-sectional shape of channel 890 may be slightly smaller than the cross-sectional shape of spine 214. In this manner, when electrode assembly 800 is clamped together around ridge 214, electrode assembly 800 forms a friction fit with ridge 214 to help prevent electrode assembly 800 from sliding proximally and distally along the length of ridge 214.

Fig. 9 is a schematic illustration showing an exploded view of an electrode assembly 800 according to another embodiment of the present invention. As shown, the electrode 840 may include a base portion 842 that may extend outwardly from the electrode 840. The first insulating housing portion 870 may also include a rim 872 that may extend inwardly near a top portion of the first insulating housing portion 870. To help secure the electrode 840 in the electrode assembly 800, the base portion 842 may be sized to have an outer peripheral length that is greater than the inner peripheral length of the rim 872. Accordingly, when the electrode 840 placed between the first insulative housing portion 870 and the second insulative housing portion 870 and the first insulative housing portion 870 are secured to the second insulative housing portion 880, the electrode 840 may be secured in place because the base portion 842 and the rim 872 prevent the electrode 840 from falling out of the first insulative housing portion 880.

Fig. 10A and 10B are schematic illustrations showing a perspective view of a first insulating case portion 870 of the electrode assembly 800. As shown, the first insulating housing portion 870 may include a passage opening 874, which may generally be a cut-out portion of the first insulating housing portion 870 positioned between the two sidewalls 879. The passage opening 874 may be sized to receive at least a portion of the ridge 214. The channel opening 874 may include rounded edges to help reduce stress concentrations and to help reduce the likelihood of damage to the ridge 214 by the first insulating housing portion 870.

The first insulative housing portion 870 may also include a female connector 878 sized to receive a corresponding male connector 888 of the second insulative housing portion 880 (as shown and described with respect to fig. 10C and 10D). The female connector 878 may be positioned in or on a sidewall 879 of the first insulating housing portion 870 such that when the electrode assembly 800 is secured to the spine 214, the female connector 878 may be positioned adjacent one side of the spine 214. The female connector 878 may include a narrowed portion 876 that may be configured to allow the male connector 888 to be pushed into the female connector 878 but to prevent removal of the male connector 888 from the female connector 878 once assembled. For example, the narrow portion 876 may be sloped to a point that includes a distance between opposite edges of the narrow portion 876 that is less than the diameter of the male connector 888. Thus, the narrow portion 876 may allow the male connector 888 to slide through the narrow portion 876 in a first direction but prevent the male connector 888 from sliding through the narrow portion 876 in a second direction. The first insulative housing portion 870, the second insulative housing portion 880, or both, may be made of an elastic material to allow the narrow portion 876, the male connector 888, or both, to deflect as the male connector 888 is pushed into the female connector 878.

Fig. 10C and 10D are schematic illustrations showing a perspective view of the second insulating case portion 880 of the electrode assembly 800. As previously described, the second insulative housing portion 880 may include a male connector 888 that may protrude from the second insulative housing portion 880 and be configured to interlock with a female connector 878 of the first insulative housing portion 870. Similar to the channel portion 874 of the first insulative housing portion 870, the second insulative housing portion 880 may further include a channel portion 884 that may be sized to receive the ridges 214. The channel portion 884 may be configured to align with the channel portion 874 such that the ridge 214 may be positioned between the first insulative housing portion 870 and the second insulative housing portion 880 when assembled.

The channel portion 884 can include a rounded lip 886 that can be positioned near the outer edge of the channel portion 884 to help reduce stress concentrations and reduce the likelihood of the second insulating housing portion 880 damaging the ridge 214. The rounded lip 886 may include a rounded edge and be generally concave in shape such that the rounded lip 886 may allow the ridges 214 to flex as it transitions between the expanded and collapsed forms.

The second insulating housing portion 880 may include a wire hole 882, which may be configured to receive a wire of the electrode assembly 800. For example, wires may be disposed along the ridges 214 and then passed through the wire holes 882 and electrically connected to the electrodes 840. The wire may be soldered, crimped, or otherwise connected to electrode 840. The wire aperture 882 may include a rounded edge to help reduce stress concentrations and reduce the likelihood of the second insulative housing portion 880 damaging the wire. Alternatively or additionally, wire holes 882 may be used for electrode 840 alignment. For example, the electrode 840 may have pin-like projections that will be inserted through holes included in the first insulating housing portion 870 and the second insulating housing portion 880.

Although described as a first insulative housing portion 870 having a female connector 878 and a second insulative housing portion 880 having a male connector 888, one skilled in the art will recognize that both may be switched. In other words, the first insulative housing portion 870 may have a male connector 888 and the second insulative housing portion 880 may have a female connector 878 without departing from the scope of this disclosure. In addition, the electrode assembly 800 may have any number of female 878 and male 888 connectors that will be suitable for a particular application.

Although the electrode assembly 800 and its components are shown in fig. 8A through 10D as having a particular shape, those skilled in the art will appreciate that electrode assemblies 300 having other shapes are contemplated. For example, the electrode assembly 300 may include a generally circular, rectangular, triangular, polygonal, elliptical, or any other suitable shape without departing from the scope of the present disclosure.

Fig. 11A and 11B are schematic illustrations showing various insulating sheaths 1180A, 1180B of a given medical device 22, according to embodiments of the present invention. Fig. 11A is a front view of insulating jackets 1180A, 1180B, while fig. 11B is a perspective view thereof. The insulating jackets 1180A, 1180B may be made of a biocompatible electrically insulating material such as a polyamide-polyether (Pebax) copolymer, polyethylene terephthalate (PET), polyurethane, polyimide, parylene, silicone, or the like. Insulating jackets 1180A, 1180B may also include filler materials, such as PTFE, boron nitride, or the like. Insulating sheaths 1180A, 1180B may help insulate struts and/or wires passing through insulating sheaths 1180A, 1180B from electrode 40 to prevent arcing from electrodes 40, 340 and/or 840 to struts and/or wires passing through insulating sheaths 1180A, 1180B.

As shown in fig. 11A and 11B, insulating jackets 1180A, 1180B may include a substantially trapezoidal cross-sectional shape. The insulating sheath may be comprised of a single lumen or multiple lumen configuration. The multi-lumen sheath may be configured such that the alloy frame and wire share a single lumen, while the second lumen may be used for irrigation. The alloy frame and wire may also occupy separate lumens, as described. For these designs, the insulating sheath may be continuous (individual sleeves extending from near the distal end of each alloy frame strut), segmented (bridging between electrode gaps), or a combination of both. Further, insulating jackets 1180A, 1180B may include first lumens 1182A, 1182B and second lumens 1184A, 1184B. The first lumens 1182A, 1182B may be configured to receive struts, while the second lumens 1184A, 1184B may be configured to receive wires, or vice versa. In other examples, the first lumens 1182A, 1182B and the second lumens 1184A, 1184B may each be configured to receive one or more wires that may be connected to one or more electrodes 40. Further, as shown in fig. 10B, insulating sheaths 1180A, 1180B may include holes 1186A, 1186B through which wires may be electrically connected to electrode 40. Although shown in fig. 10B as being near the bottom of insulating jackets 1180A, 1180B, holes 1186A, 1186B may be positioned near the top or sides of insulating jackets 1180A, 1180B. Further, insulating jackets 1180A, 1180B may include a plurality of holes 1186A, 1186B, wherein each hole is disposed on the same side of the insulating jacket (i.e., top, bottom, left side, right side) or on a different side of the insulating jacket, depending on the application.

Fig. 12A and 12B are schematic illustrations showing a side view of a ridge 214 of a given medical device 22, according to an embodiment of the invention. As will be appreciated, the spine 214 shown in fig. 12A and 12B is a single spine 214 and may represent multiple spines 214 of the basket assembly 38 described herein. In other words, the plurality of ridges 214 forming the basket assembly 38 may each be configured to form the same or similar shape when in the expanded form such that the plurality of ridges 214 together form the desired shape. To illustrate, the ridges 214 as shown in fig. 12A may be configured to form an approximately circular shape when in the expanded form. Thus, when combined with other ridges 214 to form basket assembly 38, the plurality of ridges 214 may be configured to form an approximately spherical shape when basket assembly 38 is in the expanded form. As another example, the ridges 214 shown in fig. 12B may be configured to form an approximately oval shape when in the expanded form. Thus, when combined with other ridges 214 to form the basket assembly 38, the plurality of ridges 214 may be configured to form an approximately spheroid shape when the basket assembly 38 is in the expanded form. Although not every variation of shape is shown or described herein, those skilled in the art will appreciate that the ridges 214 may be further configured to form other various shapes suitable for a particular application. Further, the medical device 22 may include one or more ridges of alternative shapes that may be formed to have a shape with a profile similar to the shape of the ridges 214 shown in fig. 12A or 12B.

By including ridges 214 configured to form various shapes when in the expanded form, basket assembly 38 may be configured to position various electrodes 40 attached to ridges 214 at various locations, with each location being closer to or farther from the distal end of flexible insertion tube 30. For example, when basket assembly 38 is in the expanded form, electrode 40 attached to ridge 214 shown in fig. 12A near the middle of ridge 214 will be farther from the distal end of flexible insertion tube 30 than ridge 214 shown in fig. 12B.

Fig. 13A and 13B are schematic illustrations showing cross-sectional views of a given line 1300, 1350 connectable to a given electrode 40, 340, 840 according to embodiments of the invention. Fig. 13A shows a solid core wire 1300. Fig. 13B shows a stranded wire 1350. Each wire 1300, 1350 may extend through at least a portion of the tubular shaft 84. The solid core wire 1300 may include a conductive core material 1302 and a conductive cover material 1304 surrounding the conductive core material 1302. Similarly, the stranded wires 1350 may include strands, each strand including a conductive core material 1352 and a conductive cover material 1354 surrounding the conductive core material 1352. Each wire 1300, 1350 may include an insulating sheath 1306 surrounding the conductor. Lines 1300, 1350 may be configured to withstand a voltage difference of adjacent lines sufficient to deliver an IRE pulse. Preferably, the wires 1300, 1350 can withstand at least 900V, and more preferably at least 1800V, between adjacent wires. To reduce the likelihood of dielectric breakdown between conductors of adjacent lines, the conductive cover materials 1304, 1354 may have a lower conductivity than the core materials 1302, 1352.

The insulating sheath 1306 may be configured to have a temperature rating between 150 degrees celsius and 200 degrees celsius such that the electrically insulating sheath 1306 melts or degrades (e.g., char and chip) during welding of the wire 1300 to the electrode 40 (e.g., at a temperature of 300 degrees celsius), and thus the insulating sheath 1306 of the wire 1300 does not need to be mechanically stripped. In other examples, the insulating sheath 1306 may have a temperature rating of greater than 200 degrees celsius to prevent the electrically insulating material 1302 from melting or degrading (e.g., charring and chipping) during manufacture and/or during use of the medical probe 22. The insulating sheath 1306 may be mechanically stripped from the wire 1300 before the wire 1300 is electrically connected to the electrode 40.

Fig. 14 is a flow chart illustrating a method 1400 of manufacturing the basket assembly 38 in accordance with an embodiment of the present invention. The method 1400 may include aligning 1402 the ridges 214 of the expandable basket assembly 38 with the first insulating portion and the second insulating portion. For example, as described herein, the method 1400 may include aligning 1402 the ridges 214 with the electrode 340, the first gasket 350, and the second gasket 360. As another example, as described herein, the method 1400 may include aligning 1402 the ridges 214 with the electrode 840, the first insulative housing portion 870, and the second insulative housing portion 880.

The method 1400 may also include placing 1404 the ridge 214 between the first insulating portion and the second insulating portion. For example, as described herein, the ridge 214 may be positioned between the first gasket 350 and the second gasket 360. As another example, as described herein, the ridge 214 may be placed between the first insulative housing portion 870 and the second insulative housing portion 880, with the electrode 840 disposed between the ridge 214 and the first insulative housing portion 870.

The method 1400 may further include interlocking 1406 the electrodes 340, 840, the first insulating portion (i.e., the first gasket 350 or the first insulating housing portion 870), and the second insulating portion (i.e., the second gasket 360 or the second insulating housing portion 880) together until the electrodes are secured to the ridges 214. For example, method 1400 may include interlocking electrode 340, first gasket 350, and second gasket 360 together until electrode assembly 300 is secured in place by swage fitting 344 engaging second gasket 360. As another example, the method 1400 may include pushing the first insulative housing portion 870 with the second insulative housing portion 880 until the male connector 888 engages the female connector 878 and the electrode assembly 800 is secured to the spine 214.

As will be appreciated by those of skill in the art, the method 1400 may include any of the various features of the disclosed technology described herein and may vary depending on the particular configuration. Thus, the method 1400 should not be interpreted as limited to the specific steps and sequence of steps explicitly described herein.

The disclosed technology described herein may be further understood in light of the following clauses:

clause 1: a medical probe, comprising: a tubular shaft having a proximal end and a distal end, the tubular shaft extending along a longitudinal axis; and an expandable basket assembly coupled to the distal end of the tubular shaft, the basket assembly comprising: at least one ridge extending along the longitudinal axis and configured to flex radially outward from the longitudinal axis when the expandable basket assembly transitions from the collapsed to the expanded form; and a plurality of electrode assemblies, each of the plurality of electrode assemblies attached to the at least one ridge and comprising: an electrode; a first electrically insulating portion electrically isolating the electrode from the at least one ridge; and a second electrically insulating portion electrically isolating the electrode from the at least one ridge, the electrode, the first electrically insulating portion, and the second electrically insulating portion interlocking to the at least one ridge such that the plurality of electrode assemblies are prevented from sliding proximally or distally along the length of the at least one ridge.

Clause 2: the medical probe of clause 1, wherein the at least one ridge comprises a retaining ring to which a respective electrode assembly of the plurality of electrode assemblies is interlocked.

Clause 3: the medical probe of clause 1 or 2, wherein the electrode comprises a protrusion configured to interlock with the second electrically insulating portion.

Clause 4: the medical probe of clause 3, wherein the protrusion extends through the retaining ring, thereby preventing the electrode assembly from sliding along the length of the at least one ridge.

Clause 5: the medical probe of clause 4, wherein the projection further comprises a swaged fitting.

Clause 6: the medical probe of any one of clauses 1-4, wherein: the first electrically insulating portion includes a first gasket; and the second electrically insulating portion comprises a second gasket.

Clause 7: the medical probe of clause 6, wherein the first and second gaskets are configured to prevent the electrode from contacting and electrically isolating the electrode from the at least one ridge.

Clause 8: the medical probe of clause 7, wherein the second washer includes a lip configured to extend inwardly into the retaining ring to prevent the electrode from contacting the at least one ridge.

Clause 9: the medical probe of clause 1, wherein: the first electrically insulating portion includes a first housing portion; and the second electrically insulating portion includes a second housing portion.

Clause 10: the medical probe of clause 9, wherein the first housing portion and the second housing portion are configured to interlock to secure the electrode to the at least one ridge.

Clause 11: the medical probe of clause 10, wherein: the second housing portion includes a male connector; and the first housing portion includes a female connector configured to receive the male connector and facilitate interlocking of the first housing portion with the second housing portion.

Clause 12: the medical probe of any one of clauses 9-11, the first housing portion comprising a rim configured to receive the electrode.

Clause 13: the medical probe of clause 12, the electrode further comprising a base portion configured to retain the electrode in the rim of the first housing portion.

Clause 14: the medical probe of clause 13, wherein the base portion includes an outer peripheral length that is greater than an inner peripheral length of the rim.

Clause 15: the medical probe of any of clauses 1-14, wherein the electrode is electrically connected to a wire of the medical probe.

Clause 16: the medical probe of clause 15, wherein at least a portion of the wire comprises: a conductive core material having a first conductivity; a conductive cover material having a second conductivity less than the first conductivity, the conductive cover material surrounding the conductive core material; and an insulating sheath surrounding the conductive covering material.

Clause 17: the medical probe of any of clauses 15 or 16, wherein at least a portion of the wire comprises a plurality of strands; and an insulating sheath surrounding the plurality of strands, and wherein each strand of the plurality of strands comprises: a conductive core material having a first electrical conductivity; and a conductive cover material having a second conductivity less than the first conductivity, the conductive cover material surrounding the conductive core material.

Clause 18: the medical probe of any of clauses 1-17, wherein the at least one ridge comprises nitinol.

Clause 19: the medical probe of any of clauses 1-18, wherein the at least one ridge comprises cobalt chromium.

Clause 20: the medical probe of any of clauses 1-19, wherein the plurality of electrodes are configured to deliver an electrical pulse for irreversible electroporation, the pulse having a peak voltage of at least 900 volts (V).

Clause 21: the medical probe of any of clauses 1-20, wherein the at least one ridge is configured to form an approximately spherical basket assembly.

Clause 22: the medical probe of any of clauses 1-20, wherein the at least one ridge is configured to form a basket assembly approximating an oblate spheroid.

Clause 23: the medical probe of any of clauses 1-22, wherein the at least one ridge further comprises an electrically insulating sheath comprising a first lumen configured to receive a first wire and a second lumen configured to receive a second wire.

Clause 24: the medical probe of any of clauses 23, wherein the cross-sectional shape of the electrically insulating sheath comprises a substantially trapezoidal shape.

Clause 25: the medical probe of any one of clauses 1-24, further comprising an irrigation opening configured to deliver irrigation fluid to the plurality of electrodes.

Clause 26: a method of constructing a medical probe, the method comprising: aligning the electrode, the first insulating portion, and the second insulating portion; placing a ridge of basket conduit between the first insulating portion and the second insulating portion; and interlocking the electrode, the first insulating portion, and the second insulating portion together to secure the electrode to the spine such that the first insulating portion and the second insulating portion electrically isolate the electrode from the spine and such that the electrode, the first insulating portion, and the second insulating portion are prevented from sliding proximally or distally along the length of the spine.

Clause 27: the method of clause 26, wherein interlocking the electrode, the first insulating portion, and the second insulating portion together comprises interlocking a portion of at least one of the electrode, the first insulating portion, and the second insulating portion through the aperture of the retaining ring of the ridge.

Clause 28: the method of clause 27, further comprising aligning the electrode, the first insulating portion, and the second insulating portion with the retaining ring.

Clause 29: the method of clause 28, wherein interlocking the electrode, the first insulating portion, and the second insulating portion together comprises interlocking a protrusion of the electrode with the second insulating portion.

Clause 30: the method of clause 29, further comprising forming a swage fitting on the projection to interlock the electrode with the second insulating portion.

Clause 31: the method of clause 29, wherein interlocking the electrode, the first insulating portion, and the second insulating portion together comprises extending the tab through the retaining ring, thereby preventing the electrode from sliding proximally or distally along the length of the ridge.

Clause 32: the method of any one of clauses 26 to 31, wherein: the first insulating portion includes a first insulating washer; and the second insulating portion includes a second insulating washer.

Clause 33: the method of clause 32, further comprising:

the first insulating washer and the second insulating washer are positioned such that the electrode is electrically isolated from the ridge.

Clause 34: the method of clause 32, wherein interlocking the electrode, the first insulating portion, and the second insulating portion together comprises extending a lip of the second insulating gasket inward into the retaining ring, thereby preventing the electrode from contacting the ridge.

Clause 35: the method of clause 26, wherein: the first insulating portion includes a first insulating housing portion; and the second insulating portion includes a second insulating housing portion.

Clause 36: the method of clause 35, wherein interlocking the electrode, the first insulating portion, and the second insulating portion together comprises interlocking the first insulating housing portion and the second insulating housing portion to secure the electrode to the ridge.

Clause 37: the method of clause 36, wherein: the second insulative housing portion includes a male connector; and the first insulative housing portion includes a female connector configured to receive the male connector and facilitate interlocking of the first insulative housing portion with the second insulative housing portion.

Clause 38: the method of any one of clauses 35 to 37, the first insulating housing portion comprising a rim configured to receive the electrode.

Clause 39: the method of clause 38, wherein interlocking the electrode, the first insulating portion, and the second insulating portion together comprises retaining a base portion of the electrode in the rim.

Clause 40: the method of clause 39, wherein the base portion includes an outer peripheral length that is greater than an inner peripheral length of the rim.

Clause 41: the method of any of clauses 26 to 40, further comprising electrically connecting the electrode to a wire of the medical probe.

Clause 42: the method of clause 41, wherein at least a portion of the wire comprises a conductive core material having a first conductivity, a conductive cover material having a second conductivity less than the first conductivity, and an insulating sheath surrounding the conductive cover material, the conductive cover material surrounding the conductive core material.

Clause 43: the method of clause 41 or 42, wherein at least a portion of the wire comprises a plurality of strands; and an insulating sheath surrounding the plurality of strands, and wherein each strand of the plurality of strands comprises: a conductive core material having a first electrical conductivity; and a conductive cover material having a second conductivity less than the first conductivity, the conductive cover material surrounding the conductive core material.

Clause 44: the method of any of clauses 26-43, wherein the ridge comprises nitinol.

Clause 45: the method of any of clauses 26-43, wherein the ridge comprises cobalt chromium.

Clause 46: the method of any of clauses 26-45, wherein the electrode is configured to deliver an electrical pulse for irreversible electroporation, the pulse having a peak voltage of at least 900 volts (V).

Clause 47: the method of any of clauses 26-46, wherein the ridge is configured to form an approximately spherical basket assembly.

Clause 48: the method of any of clauses 26-46, wherein the ridge is configured to form a basket assembly approximating an oblate spheroid.

Clause 49: the method of any of clauses 26-48, wherein the ridge further comprises an electrically insulating sheath comprising a first lumen configured to receive a first wire and a second lumen configured to receive a second wire.

Clause 50: the method of any of clauses 49, wherein the electrically insulating sheath comprises a substantially trapezoidal shape.

Clause 51: the method of any of clauses 26-50, further comprising configuring the irrigation opening to deliver irrigation fluid to the electrode.

The above embodiments are cited by way of example, and the present invention is not limited to what has been particularly shown and described hereinabove. Rather, the scope of the present invention includes both combinations and sub-combinations of the various features described hereinabove as well as variations and modifications thereof which would occur to persons skilled in the art upon reading the foregoing description and which are not disclosed in the prior art.

Claims

1. A medical probe, comprising:

a tubular shaft having a proximal end and a distal end, the tubular shaft extending along a longitudinal axis; and

an expandable basket assembly coupled to the distal end of the tubular shaft, the expandable basket assembly comprising:

at least one ridge extending along the longitudinal axis and configured to flex radially outward from the longitudinal axis when the expandable basket assembly transitions from a collapsed to an expanded form; and

a plurality of electrode assemblies, each of the plurality of electrode assemblies attached to the at least one ridge and comprising:

an electrode;

a first electrically insulating portion electrically isolating the electrode from the at least one ridge; and

a second electrically insulating portion electrically isolating the electrode from the at least one ridge, the electrode, the first electrically insulating portion, and the second electrically insulating portion interlocking to the at least one ridge such that the plurality of electrode assemblies are prevented from sliding proximally or distally along the length of the at least one ridge.

2. The medical probe of claim 1, wherein the at least one ridge comprises a retaining ring to which a respective electrode assembly of the plurality of electrode assemblies is interlocked.

3. The medical probe of claim 2, wherein the electrode includes a protrusion configured to interlock with the second electrically insulating portion.

4. The medical probe of claim 3, wherein the protrusion extends through the retaining ring, thereby preventing the electrode assembly from sliding along the length of the at least one ridge.

5. The medical probe of claim 4, wherein the projection further comprises a swage fitting.

6. The medical probe of claim 1, wherein:

the first electrically insulating portion includes a first gasket; and is also provided with

The second electrically insulating portion includes a second gasket.

7. The medical probe of claim 6, wherein the first and second washers are configured to prevent the electrode from contacting and electrically isolating the electrode from the at least one ridge.

8. The medical probe of claim 7, wherein the second washer includes a lip configured to extend inwardly into the retaining ring of the at least one ridge to prevent the electrode from contacting the at least one ridge.

9. The medical probe of claim 1, wherein:

the first electrically insulating portion includes a first housing portion; and is also provided with

The second electrically insulating portion includes a second housing portion.

10. The medical probe of claim 9, wherein the first housing portion and the second housing portion are configured to interlock to secure the electrode to the at least one ridge.

11. The medical probe of claim 10, wherein:

the second housing portion includes a male connector; and is also provided with

The first housing portion includes a female connector configured to receive the male connector and facilitate interlocking of the first housing portion with the second housing portion.

12. The medical probe of claim 9, the first housing portion comprising a rim configured to receive the electrode.

13. The medical probe of claim 12, the electrode further comprising a base portion configured to retain the electrode in the rim of the first housing portion.

14. The medical probe of claim 13, wherein the base portion includes an outer peripheral length that is greater than an inner peripheral length of the rim.

15. A method of constructing a medical probe, the method comprising:

aligning the electrode, the first insulating portion, and the second insulating portion;

placing a ridge of basket conduit between the first insulating portion and the second insulating portion; and

interlocking the electrode, the first insulating portion, and the second insulating portion together to secure the electrode to the spine such that the first insulating portion and the second insulating portion electrically isolate the electrode from the spine and such that the electrode, the first insulating portion, and the second insulating portion are prevented from sliding proximally or distally along the length of the spine.

16. The method of claim 15, wherein interlocking the electrode, the first insulating portion, and the second insulating portion together comprises interlocking a portion of at least one of the electrode, the first insulating portion, and the second insulating portion through an aperture of a retaining ring of the ridge.

17. The method of claim 16, further comprising aligning the electrode, the first insulating portion, and the second insulating portion with the retaining ring.

18. The method of claim 17, wherein interlocking the electrode, the first insulating portion, and the second insulating portion together comprises interlocking a protrusion of the electrode with the second insulating portion.

19. The method according to claim 15, wherein:

the first insulating portion includes a first insulating housing portion; and is also provided with

The second insulating portion includes a second insulating housing portion.

20. The method of claim 19, wherein interlocking the electrode, the first insulating portion, and the second insulating portion together comprises interlocking the first insulating housing portion and the second insulating housing portion to secure the electrode to the spine.